The new play Oslo tells the unlikely story of how a Norwegian sociologist and his wife, a foreign minister in the title city, managed to broker the historic 1993 peace agreement between Israel and the Palestine Liberation Organization. Grounding this diplomatic cloak-and-dagger tale are Jefferson Mays and Jennifer Ehle, whose magnetism makes audiences wish these Tony winners could take on the Middle East peace process in real life. On and off stage, they’re an ideal blend of grounded charm (Ehle) and effervescent theatricality (Mays). The actors chatted about J.T. Rogers’ fact-based drama—and the fun of playing spies and diplomats—on the sunny rooftop of Lincoln Center Theater, two levels up from where the fascinating machinations of Oslo play out eight times a week.

Q: You two seem perfectly matched as husband and wife in Oslo.

JENNIFER: We love being together.

JEFFERSON: Yes, you’ve turned me into a theatrical monogamist. I don’t want to be married to anyone on stage anymore unless it’s to you.Q: How on earth did J.T. Rogers turn a complicated piece of diplomacy into a riveting three-hour-long play?

JENNIFER: It’s a bit of a miracle. He’s a bit brilliant, isn’t he?

JEFFERSON: He is, and the thing I love most is that he flies in the face of that adage about “writing what you know.” He writes about what he doesn’t know. When he’s vexed and confounded about something and wants to investigate what it means, he does that through writing plays.

JENNIFER: And [there’s] his humor: He has many spoonfuls of sugar to help the historical and political lessons go down.

Q: What’s it like to perform?

JEFFERSON: This play takes us by surprise every night, with all of its twists and turns—which sounds rather unbelievable for us to say, having been in rehearsal for five weeks and then previews, but we still don’t know what’s happening next.

JENNIFER: It’s that big. And it’s amazing to look out and see the audience really leaning forward.

JEFFERSON: Their level of engagement is astonishing, particularly since it’s three hours!Q: Jennifer played a spy in Zero Dark Thirty and MI-5, and Jefferson was a spy in J.T. Rogers’ Blood and Gifts and an FBI agent in The Americans. What’s the appeal?

JENNIFER: They’re crackling yarns.

JEFFERSON: Good yarns, yes, and I think that all actors are by nature spies in the way we skulk about and observe human behavior.

Q: Which of you would make a better diplomat?

JEFFERSON: Decidedly Jennifer. You have great leadership skills and a luminous quality that makes people feel at ease and open themselves to you.

JENNIFER: Very important for diplomacy! People do tell me things.

JEFFERSON: I’ve confessed some astonishing things to you in our short acquaintance.

Q: Jennifer, you took a break from theater and dropped out of playing Catelyn Stark in Game of Thrones [after filming the pilot]. Any regrets?

JENNIFER: No. I love the show and I’m sure I would have enjoyed being in it, but it’s impossible to have regrets when everything since then probably wouldn’t have happened if I had gone that path. I wouldn’t have done Contagion and Zero Dark Thirty and I probably wouldn’t be here right now. When we did the pilot my baby was seven months old, and when they called to say the show had been picked up, I said, “With all respect, I beg that you let me go.” I’m grateful to them, and I’m very happy.

JEFFERSON: I’m grateful you’re here!Q: What did you learn about acting from observing the career of your mother, the great Rosemary Harris?

JENNIFER: So much. Putting family first was a big one. She was so present as a mother, and I cannot imagine being otherwise, having experienced that from her. She’s constantly working and learning and sharing. I can’t do anything without thinking about things she said and trying to honor them.

Q: Jefferson, who influenced your decision to become an actor?

JEFFERSON: My wonderful parents read aloud to me a lot as a child, which in many ways was my introduction to theater. Our television broke during the Vietnam War, and they never replaced it. What they did do was pass novels around the family table. My mother was an actor, and her face would change depending on the character. I remember being riveted.

JENNIFER: Your face does that. It’s amazing.

JEFFERSON: Maybe it’s my mother’s face if I’m lucky.

Q: I must ask about your sense of style….

JENNIFER: Isn’t it wonderful?

JEFFERSON: Good heavens, I just sort of wear what I like—bits and pieces from my father and grandfather.

Q: How big is your closet?

JEFFERSON: It’s a modest size, but I have a big steamer trunk, the kind people used to travel with, and lots of pegs with hats on them in the hallway. It’s good to have a selection of hats.

Q: Jennifer’s mom is going strong at 88. Will the two of you still be on stage at that age?

JENNIFER: Oh, I hope so! If I’m alive, I will be.

JEFFERSON: When I’m 88 years old, I hope I’m on stage married to Jennifer Ehle.